[PATCH v2 2/4] mfd: Add RZ/V2M PWC core driver

Fabrizio Castro
2022-12-21T21:09:56Z

The External Power Sequence Controller (PWC) IP (found in the
RZ/V2M SoC) is a controller for external power supplies (regulators
and power switches), and it supports the following features: it
generates a power on/off sequence for external power supplies,
it generates an on/off sequence for the LPDDR4 core power supply
(LPVDD), it comes with General-Purpose Outputs, and it processes
key input signals.

The PWC is basically a Multi-Function Device (MFD), its software
support comes with a core driver, and specialized drivers for
its specific features.

This patch adds the core driver for the RZ/V2M PWC IP.

Signed-off-by: Fabrizio Castro <fabrizio.castro.jz@renesas.com>
---

v1->v2: This is a new driver, to match the relevant compatible string
and instantiate the relevant mfd device drivers

drivers/mfd/Kconfig | 14 +++++++++
drivers/mfd/Makefile | 1 +
drivers/mfd/rzv2m-pwc.c | 70 +++++++++++++++++++++++++++++++++++++++++
drivers/mfd/rzv2m-pwc.h | 18 +++++++++++
4 files changed, 103 insertions(+)
create mode 100644 drivers/mfd/rzv2m-pwc.c
create mode 100644 drivers/mfd/rzv2m-pwc.h

diff --git a/drivers/mfd/Kconfig b/drivers/mfd/Kconfig
index 30db49f31866..ac4403e4f3cb 100644
--- a/drivers/mfd/Kconfig
+++ b/drivers/mfd/Kconfig
@@ -2265,5 +2265,19 @@ config MFD_RSMU_SPI
Additional drivers must be enabled in order to use the functionality
of the device.

+config MFD_RZV2M_PWC_CORE
+ tristate "Renesas RZ/V2M PWC Core Driver"
+ select MFD_CORE
+ depends on ARCH_R9A09G011 || COMPILE_TEST
+ help
+ Select this option to enable the RZ/V2M External Power Sequence
+ Controller (PWC) core driver.
+
+ The PWC is a controller for external power supplies (regulators and
+ power switches), and it supports the following features: it generates
+ a power on/off sequence for external power supplies, it generates an
+ on/off sequence for the LPDDR4 core power supply (LPVDD), it comes
+ with General-Purpose Outputs, and it processes key input signals.
+
endmenu
endif
diff --git a/drivers/mfd/Makefile b/drivers/mfd/Makefile
index 457471478a93..e39252a2df23 100644
--- a/drivers/mfd/Makefile
+++ b/drivers/mfd/Makefile
@@ -278,3 +278,4 @@ rsmu-i2c-objs := rsmu_core.o rsmu_i2c.o
rsmu-spi-objs := rsmu_core.o rsmu_spi.o
obj-$(CONFIG_MFD_RSMU_I2C) += rsmu-i2c.o
obj-$(CONFIG_MFD_RSMU_SPI) += rsmu-spi.o
+obj-$(CONFIG_MFD_RZV2M_PWC_CORE) += rzv2m-pwc.o
diff --git a/drivers/mfd/rzv2m-pwc.c b/drivers/mfd/rzv2m-pwc.c
new file mode 100644
index 000000000000..f9055fcafda2
--- /dev/null
+++ b/drivers/mfd/rzv2m-pwc.c
@@ -0,0 +1,70 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Copyright (C) 2022 Renesas Electronics Corporation
+ *
+ * Core driver for the Renesas RZ/V2M External Power Sequence Controller (PWC)
+ */
+
+#include <linux/of.h>
+#include <linux/platform_device.h>
+#include <linux/mfd/core.h>
+#include "rzv2m-pwc.h"
+
+static const struct mfd_cell rzv2m_pwc_gpio_devs[] = {
+ { .name = "gpio_rzv2m_pwc", },
+};
+
+static const struct mfd_cell rzv2m_pwc_poweroff_devs[] = {
+ { .name = "rzv2m_pwc_poweroff", },
+};
+
+static int rzv2m_pwc_probe(struct platform_device *pdev)
+{
+ struct rzv2m_pwc_priv *priv;
+ int ret;
+
+ priv = devm_kzalloc(&pdev->dev, sizeof(*priv), GFP_KERNEL);
+ if (!priv)
+ return -ENOMEM;
+
+ priv->base = devm_platform_ioremap_resource(pdev, 0);
+ if (IS_ERR(priv->base))
+ return PTR_ERR(priv->base);
+
+ platform_set_drvdata(pdev, priv);
+
+ ret = devm_mfd_add_devices(&pdev->dev, PLATFORM_DEVID_AUTO,
+ rzv2m_pwc_gpio_devs,
+ ARRAY_SIZE(rzv2m_pwc_gpio_devs), NULL, 0,
+ NULL);
+ if (ret)
+ return ret;
+
+ if (of_property_read_bool(pdev->dev.of_node, "renesas,rzv2m-pwc-power"))
+ ret = devm_mfd_add_devices(&pdev->dev, PLATFORM_DEVID_AUTO,
+ rzv2m_pwc_poweroff_devs,
+ ARRAY_SIZE(rzv2m_pwc_poweroff_devs),
+ NULL, 0, NULL);
+
+ return ret;
+}
+
+static const struct of_device_id rzv2m_pwc_of_match[] = {
+ { .compatible = "renesas,rzv2m-pwc" },
+ { /* sentinel */ }
+};
+MODULE_DEVICE_TABLE(of, rzv2m_pwc_of_match);
+
+static struct platform_driver rzv2m_pwc_driver = {
+ .probe = rzv2m_pwc_probe,
+ .driver = {
+ .name = "rzv2m_pwc",
+ .of_match_table = of_match_ptr(rzv2m_pwc_of_match),
+ },
+};
+module_platform_driver(rzv2m_pwc_driver);
+
+MODULE_SOFTDEP("post: gpio_rzv2m_pwc rzv2m_pwc_poweroff");
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("Fabrizio Castro <castro.fabrizio.jz@renesas.com>");
+MODULE_DESCRIPTION("Renesas RZ/V2M PWC core driver");
diff --git a/drivers/mfd/rzv2m-pwc.h b/drivers/mfd/rzv2m-pwc.h
new file mode 100644
index 000000000000..8f3d777557c9
--- /dev/null
+++ b/drivers/mfd/rzv2m-pwc.h
@@ -0,0 +1,18 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * Copyright (C) 2022 Renesas Electronics Corporation
+ */
+
+#ifndef __LINUX_RZV2M_PWC_H__
+#define __LINUX_RZV2M_PWC_H__
+
+#define PWC_PWCRST 0x00
+#define PWC_PWCCKEN 0x04
+#define PWC_PWCCTL 0x50
+#define PWC_GPIO 0x80
+
+struct rzv2m_pwc_priv {
+ void __iomem *base;
+};
+
+#endif /* __LINUX_RZV2M_PWC_H__ */
--
2.34.1